05 August 2013 From the archives: THE LOONS OF NEW ENGLAND by Ed Grant

loon2_iconI’ve been going through a raft of documents on a CD that David Hodsdon gave me recently and I came across this piece written by Ed Grant and decided it needed to be posted. I don’t know if it was ever published anywhere, but it certainly deserved to be. Perhaps he wrote it for use in a newsletter. In any event, his recent passing makes this piece seem all the more poignant. I hope you enjoy reading it as much as I did.

by Ed Grant

The Common Loon (Gavia Immer)

There is no other sound quite like it, the tremulous wail that floats across a northern lake at dawn, the haunting voice of the northern wilds.

Few people can hear the call of the common loon without being moved, it is truly the sound of the north woods, the wail of the wilderness, and for many visitors to New England, hearing one laugh in the night is a high point of a trip.

The common loon, with its necklace of white and checkerboard pattern on the back, is the species that comes to most people’s mind when they think of loons. There are four other species, the yellow-billed, the arctic, the Pacific and the red-throated, but only the common loon is found south of Canada in the summer, with the southern edge of its breeding range stretching from the Adirondacks through northern Vermont and New Hampshire to Maine. It is strictly a warm-weather resident in the region’s inland, migrating in late fall to the sea from the Maritimes to Florida.

Taxonomically, loons are ranked among the most primitive of birds, yet there is nothing unsophisticated about them, from their elegant plumage to their many physical adaptations to suit them for an aquatic lifestyle. The legs, which are powerfully muscular, are set far back on the body. This provides them maximum strength for swimming but forces them to push along on their breasts when they are on land. The wings are kept folded underwater, and the loon propels itself with sweeps of its webbed feet. In the forward stroke, the flattened tarsi, or leg bones, cut resistance by the water.

In fact, almost everything about a loon’s body helps it dive and swim. It has the ability to store unusually large amounts of oxygen in its muscle tissue just before plunging under water. Many of its bones are solid, rather than hollow as in most birds, resulting in a specific gravity close to that of water, so the loon can slip under without a ripple when it needs to escape quietly.

Loons have been caught in fishing nets more than 200 feet deep, but most of their time is spent in shallow water, where they dive for small fish, their primary prey. Cruising slowly along the surface, the loon will repeatedly stick its head underwater, watching for fish. When it sees a school it dives with a quick thrust of both legs, arching down like a dolphin. Although loons will catch game fish like brook trout, they more often tend to capture slower prey like small catfish, minnows and suckers. The also will eat lizards, frogs and other aquatic animal life and when animal life is not available, they survive very well on aquatic plants, eating roots, seeds and other parts of plants.

Loons are good flyers, using short, powerful wing beats to propel their long aerodynamic bodies for long distances at speeds estimated at up to 60 miles per hour. However, getting out of the water isn’t easy for them. It requires considerable open water from which to get airborne by running and flapping. They cannot get airborne at all from land or ice.

Loons generally return to their summer lake shortly after ice out. Soon after they return from their wintering grounds loon pairs pick a nest site. They often return to the same secluded cove they used in past years. The nest, a low flattened bowl of sedges and grasses built right along the water, and the eggs, normally two, are laid around Memorial Day. Incubation takes about a month, and the chicks can swim almost from birth. For the rest of the summer they stay close to their parents, eventually learning to dive and hunt on their own.

Vocalizations play an important role during the breeding season, keeping loon pairs together and delineating their territory. Ornithologists recognize four or five different calls, including the famous “laugh” and a longer and more complex version known as the “yodel” that loons use to call. They also have a low short call that they use to communicate when they are near each other.

Although you may hear loons call at anytime of the day during April, they will be most vocal at dawn and dusk and, if there is a bright moon, they may well call straight through the night. Some people can imitate a loon call well enough to draw a bird close, but this (or the use of tape-recorded calls) should be avoided since it disrupts the loon’s routine and may leave its nest or chicks vulnerable to predators.

Loon chicks don’t have a problem free early life. They are preyed upon by eagles, turtles, foxes and coons and, when very young, can’t dive to escape predators.

Common loons breed throughout the northern half of the region, often picking remote back-county lakes. Remember that June is the height of the breeding season, and you should never approach an area you suspect of harboring a loon nest.